JPH10129079A - Image-forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an erroneous writing that a program is written from an external memory to a memory on a control part for storage of programs, by comparing an identification code proper to the control part with an identification code stored in the external memory and writing the program stored in the external memory only when the codes agree. SOLUTION: The apparatus has FLASHROMs 126, 127 as a memory storing an identification code proper to a control part 82 and provided for storing programs, an IC card connector CN308 as a means for connecting an IC memory card which is an external memory storing a program for rewriting the memories 126, 127 and an identification code with the control part 32, and an MPU 81 as a means for comparing the identification code proper to the control part 82 and the identification code stored in the external memory and writing the program stored in the external memory to the memories 126, 126 only when the identification codes are equal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a control unit having a memory for storing a program.

[0002]

2. Description of the Related Art Conventionally, in a printer or the like, a method for rewriting the contents of a program storage memory on a control board constituting a control unit is to detect whether or not an external memory is connected to the control board, When an external memory is connected, the program on the external memory side is automatically executed, and the program for writing from the external memory to the program storage memory on the control board is automatically executed to store the program on the control board. Rewrite the contents of the memory on the control board by rewriting the contents of the memory, or by directly executing the write program of the program storage memory on the control board, or by copying it to the work area and executing from there Methods are known.

In each of these methods, only a program is directly written from an external memory to a program storage memory on a control board. In addition, a system is used in which writing of a program from an external memory to a program storage memory on an extension board is performed separately and independently for each extension board. Some control boards and expansion boards have a nonvolatile memory in which adjustment data and the like are stored.

Japanese Patent Laid-Open Publication No. 1-112424 discloses an electronic apparatus in which a program is downloaded using an input port of a laser printer to facilitate software version-up. . Japanese Patent Application Laid-Open No. Hei 1-246652 discloses a program which enables a low-cost apparatus and a highly flexible program to be created by downloading a control program from a host CPU to a memory while keeping a microprocessor in an initial state. The loading method is described.

[0005] Japanese Patent Application Laid-Open No. 1-175023 discloses that when a power is turned on, a download memory is not used, a portion of the download memory is also used as a reception buffer, and a memory configuration is dynamically changed when necessary to secure a download area. Describes a printer memory control method for improving operability and effectively using a memory. JP-A-1-17
Japanese Patent No. 3222 discloses an initial value setting device for a printer memory that performs an upload and a download to and from a current status memory using a master status memory to set an initial value that matches the memory content and the printer status. Is described.

[0006]

In the above-described method of writing the contents of the external memory to the memory on the board, for example, when the external memory is a general-purpose component such as an IC memory, it can be used in common by a plurality of boards. There was a possibility that a program was erroneously written from an external memory to a board different from the target board. When a nonvolatile memory for storing adjustment data and the like is provided on the board,
The runaway of the program erroneously written to the memory may destroy the adjustment data and the like in the nonvolatile memory.

Further, in a printer or the like having a plurality of extension boards, writing of a program from an external memory to a program storage memory on the extension board is performed separately and independently for each extension board. Writing a program from the memory to the program storage memory on the expansion board may have caused a board mistake or an operation mistake.

According to the present invention, it is possible to prevent erroneous writing of a program from an external memory to a program storage memory on a control unit, prevent destruction of the contents of a nonvolatile memory, and improve operability. It is an object of the present invention to provide an image forming apparatus capable of writing a program from an external memory to a program storage memory on a control unit at low cost and at high speed.

[0009]

In order to achieve the above object, the invention according to claim 1 is mounted on a control unit for controlling the operation of the entire machine, is rewritable, and has a unique configuration. A memory for storing a program in which an identification code is stored, means for connecting the control unit to an external memory in which a program for rewriting the memory for storing the program and an identification code are stored, and a unique Means for comparing an identification code with an identification code stored in the external memory and for writing a program stored in the external memory into the program storage memory only when these identification codes are equal to each other This prevents erroneous writing of a program from the external memory to the program storage memory on the control unit, and destroys the contents of the nonvolatile memory. It is possible to prevent.

According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, a configuration is provided in which a predetermined composite function can be realized by adding a plurality of extension boards. The unique identification code of each of the extension boards is stored in a rewritable memory, and the identification code stored in the internal memory of the plurality of extension boards is stored in an external memory connected to the control unit. Means for writing the program stored in the external memory to the internal memory of the extension board that matches the identification code stored in the external memory. Erroneous writing of the program can be prevented, and operability can be improved.

According to a third aspect of the present invention, in the image forming apparatus according to the second aspect, the data communication means for writing the program stored in the external memory to the internal memory of the extension board is a signal of image data. It is also used as a line, and can write a program from an external memory to a program storage memory on the control unit at low cost and at high speed.

[0012]

FIG. 2 schematically shows an embodiment of the invention according to claims 1 to 3. This embodiment is an embodiment of an image forming apparatus composed of a compound digital copying machine, and has a copying machine main body 11, an automatic document feeder 12, a sorter / stapler 13 which is a sorting device with a stapler, and a duplex reversing unit 14. . The copier main body 11 has a scanner unit, an image processing unit, an image forming unit (plotter unit), and the like, and a peripheral device such as a sorter / stapler 13, a duplex unit 14, a paper feeding bank described later, and a large-volume paper feeding device are selectively available. Connected to.

The scanner unit is provided with a light source 15 comprising an X lamp, a reflecting mirror 16 and a first mirror 17, and is driven by a scanner motor at the time of scanning a document to move at a constant speed; A second carriage, which is provided with a second mirror 18 and a third mirror 19, is driven by a scanner motor at the time of scanning of the original, and moves at half the speed of the first carriage.

The first carriage and the second carriage optically scan a document (not shown) on the document table 20, illuminate the document on the document table 20 with the light source 15 and the reflecting mirror 16, and form a reflected light image on the document table. An image is formed on the one-dimensional solid-state imaging device 23 via the first mirror 17, the second mirror 18, the third mirror 19, the color filter 21, and the lens 22, and photoelectrically converted.

A CCD is used as the one-dimensional solid-state imaging device 23. An image signal from the CCD 23 is transmitted to an A / D (not shown).
The data is A / D converted by the converter and output to the image processing board 24 constituting the image processing unit. The image processing board 24 performs various kinds of image processing (binarization, multi-level gradation processing, scaling processing, editing, etc.) on the image signal from the A / D converter of the scanner unit to form a set of light spots. The signal is converted into a corresponding digital signal and output to the plotter unit.

In this embodiment, in order to obtain a color image signal in the scanner section, a CCD
A color filter 21 that transmits only light of a required color is disposed in the middle of the optical path up to 3 so that it can be taken in and out. The color filter 21 is moved in and out of the optical path in accordance with the scanning of the document on the document table 20. In response to this, functions such as multiple transfer and double-sided copy work to create a variety of copies.

Further, in the plotter section of the copying machine main body 11, the image signal after image processing from the image processing board 24 is raster-scanned to the photosensitive drum 25 by a writing section as exposure means in the form of a set of light spots. Written. In the writing section, the semiconductor laser is driven by an image signal after image processing from the image processing substrate 24 by a semiconductor laser driving circuit, and outputs a laser beam having an intensity corresponding to the image signal. The light is converted into a parallel light beam by a lens, shaped into a light beam having a predetermined shape by an aperture member, and then enters a deflector 30 formed of a polygon mirror in a form compressed in a sub-scanning direction by a first cylinder lens.

The polygon mirror 30 has a precise polygonal shape, and is rotated by a polygon motor 31 in a fixed direction at a fixed speed. The rotation speed of the polygon mirror 30 is determined by the rotation speed of the photosensitive drum 25, the writing density of the writing unit, and the number of surfaces of the polygon mirror 30. The laser light from the first cylinder lens is deflected in the main scanning direction by the polygon mirror 30 and fθ
The light is incident on an image carrier made of a photoconductor, for example, a photoconductor drum 25 via a lens 33 and a mirror 35.

The fθ lens 33 converts the scanning light from the polygon mirror 30 at a constant angular velocity so as to scan the photosensitive drum 25 at a constant speed, and forms an image on the photosensitive drum 25 so as to have a minimum light spot. Further, the tilt correction of the polygon mirror 30 is also performed. Further, the laser light passing through the fθ lens 33 is reflected by the synchronization detecting mirror outside the image area and detected by the synchronization detecting sensor.

The signal from the synchronization detecting sensor is used as a synchronization signal for performing cueing in the main scanning direction. After a predetermined time from the synchronization signal, the image signal after image processing from the image processing board 24 is equivalent to one line. The semiconductor laser is outputted and driven by the semiconductor laser drive circuit according to the image signal. Such an operation is repeated, and one image is written on the photosensitive drum 25.

A photosensitive layer is formed on the peripheral surface of the photosensitive drum 25. The photosensitive layer is formed of an organic photosensitive member which is sensitive to laser light having a wavelength of 780 nm from a semiconductor laser.
Although there are α-Si, Se-Te and the like, an organic photoreceptor is used in this embodiment. Generally, when writing to a photosensitive drum by laser light, there are a negative / positive process of applying light to an image portion on the photosensitive drum and a positive / positive process of applying light to a background portion on the photosensitive drum. In the present embodiment, a negative / positive process is employed.

The charging charger 39 serving as charging means includes:
It is of a scorotron type having a grid on the photosensitive drum 25 side, and uniformly charges the surface of the photosensitive drum 25 negatively. The photoreceptor drum 25 is driven to rotate by a main motor and is uniformly charged by a charging charger 39, and then is exposed by irradiating a laser beam from a mirror 35 of a writing section to form an electrostatic latent image. In this case, the photosensitive drum 25 has, for example, a background portion of -750 V or more.
-800V, and the image portion becomes about -500V.

A developing bias voltage of -500 V to -600 V is applied to the developing roller from a high voltage power source, and an electrostatic latent image on the photosensitive drum 25 is transferred to the main developing device 40 and the sub developing device 41 as developing means. 40 and the sub-developing device 41 develops the image with negatively charged toner to form a visible image. The main developing device 40 supplies a developer composed of black toner and carrier to the photosensitive drum 25 by a developing roller, and a toner replenishing device 42
Is supplied with black toner. The sub-developing unit 41 supplies a developer composed of a color toner of a color other than white and black and a carrier to the photosensitive drum 25 by a developing roller, and the toner replenisher 43 supplies color toner.

The main developing device 40 and the sub developing device 41 are selectively moved to a developing position for developing the electrostatic latent image on the photosensitive drum 25 by the contact / separation function, and are usually retracted from the developing position. I have. The developing operations of the main developing device 40 and the sub developing device 41 are performed by selecting color information to read the original by switching the color filters 21 in the scanner section, performing multiple transfer of the transfer paper transport system,
Multifunctional color copying and color editing are realized selectively by combining with the double-side copying function. When developing three or more colors for the electrostatic latent image on the photosensitive drum 25, a method of arranging three or more developing devices around the photosensitive drum 25, and switching by rotating the three or more developing devices. A revolver method of moving to a developing position may be employed.

On the other hand, when any one of the paper feeding devices 44, 45, and 46 using a plurality of paper feeding cassettes is selected and the start button of the operation unit is pressed, the transfer paper in the selected paper feeding cassette is selected. Turns on the paper feed clutch and feed roller 4
Paper is fed by any one of 7, 48, and 49. This paper feeding is performed until the leading edge of the transfer paper reaches the registration roller 50 and is detected by the registration sensor 51.

In the manual feed mode, the manual pick-up roller 80 feeds transfer paper manually fed from a manual feed table (not shown) to the paper feed roller 47 when the manual feed solenoid is turned on. The transfer paper is fed by the paper feed roller 47 when the manual paper feed clutch is turned on. This paper feed is performed until the leading edge of the transfer paper reaches the registration roller 50 and is detected by the registration sensor 51.

The registration roller 50 sends out the transfer paper with its leading edge aligned with the visible image on the photosensitive drum 25. The transfer paper is positively charged by a transfer charger 52 as a transfer unit, a developed image on the photoconductor drum 25 is transferred, and is subjected to AC charge removal by a separation charger 53, so that the separation claw 5 is transferred.
4 separates from the photosensitive drum 25.

Then, the transfer paper is conveyed by a conveying device 55, and a fixing device 5 having a fixing roller and a pressure roller.
6 fixes the visible image. The residual toner is removed from the photosensitive drum 25 by the cleaning device 58, and the residual potential is erased by the discharge lamp 59, so that the photosensitive drum 25 can be reused.
The photo sensor (P sensor) 60 is disposed between the main developing device 40 and the transfer charger 52, and optically detects the reflection density on the surface of the photosensitive drum 25. The writing section writes a black or halftone pattern on the photosensitive drum 25 at a predetermined timing to form an electrostatic latent image of the pattern, and the electrostatic latent image is formed by the main developing device 40 or the sub developing device 41.
And becomes a visible image of the pattern.

The developing ability control device outputs the output signal of the photosensor 60 to the developed image of the pattern and the photosensitive drum 2
The developing capability of the main developing device 40 or the sub developing device 41 is determined from the ratio of the output signal of the photo sensor 60 to the background portion of the toner supply device 5, and based on the result, the toner replenishing device 42 or the The main developing device 40 or the sub developing device 41 is supplied with toner from the toner developing device 42 or the toner replenishing device 43 to control the developing ability of the main developing device 40 or the sub developing device 41 to be constant.

The transfer paper from the fixing device 56 is guided to the sorting device 13 by the switching claws 61 during normal copying, and is discharged to the sorting device 13 as a copy. At the time of multiple copying, the transfer paper from the fixing device 56 is supplied to the switching claws 61 and 6.
The sheet is guided to the lower side by 2 and 63, passes through the sheet re-feeding loop 64, is re-supplied to the registration roller 50, and the transfer and fixing of the visible image are performed again.

At the time of double-sided copying, there are a case where double-sided copying is performed only by the copying machine body 11 and a case where double-sided copying is performed using the double-sided copying unit 14. The transfer paper from the fixing device 56 is guided to the tray 65 by the switching claws 61, 62, and 63, and then sent in the reverse direction by the roller 66 when the intermediate clutch is turned on, and is fed to the refeeding loop 64 by the switching claw 63. By being fed, the sheet is turned upside down, re-fed to the registration roller 50, and the transfer and fixing of a visible image on the back surface are performed in the same manner.

Further, in the copying machine body 11, in the normal mode, the original is copied as described above. However, when the operator sets the interrupt mode in the operation unit during the copying in the normal mode. When the operator replaces the original on the original table 20 with the original to be interrupt-copied, the original on the original table 20 is copied in the same manner by pressing the interrupt key of the operation unit. After the interruption copy is completed, the operator sets the platen 2
The copy operation in the normal mode is resumed by exchanging the original on 0 with the original and pressing the interrupt key of the operation unit.

The automatic document feeder 12 is pivotally supported by the copier main body 11 so as to be able to open and close the document table 20 of the copier main body 11. The user can use the automatic document feeder 12 as a pressure plate, raise the automatic document feeder 12 from above the platen 20, set a document on the platen 20 by hand, and then place an automatic The document feeder 12 can be placed in place of the pressure plate.

Further, the automatic document feeder 12 is
When the original is lowered to zero, the originals are fed one by one to the original platen 20 of the copying machine main body 11 and discharged after copying. In this case, the originals are stacked on an original feeder table 67 and are aligned in the width direction by a side guide 68. The originals on the original feeder board 67 are fed one by one by a feed roller 69, and sent to the original stand 20 of the copying machine main body 11 by the transport belt 70. When copying of the set number of originals on the original platen 20 is completed, the originals are discharged to the discharge tray 71 by the transport belt 70.

When two-sided copying is performed only by the copying machine body 11, two-sided copying is performed for each sheet. When two-sided copying is performed using the two-sided copying unit 14, a plurality of originals are collected. Can be copied one by one.
When performing duplex copying using the duplex copying unit 14, the transfer paper from the fixing device 56 is guided to the duplex copying unit 14 by the switching claws 61 and 62, discharged to the tray 73 by the discharge rollers 72, and accumulated. You. At that time, the transfer paper is aligned vertically and horizontally by a feed roller 74 and a side alignment guide 75. The transfer paper stacked on the tray 73 is re-fed by the re-feed roller 76 during backside copying, and the switching claws 62,
After being sent to the re-feeding loop 64 by the 63 and fed back to the registration roller 50, the transfer and fixing of the visible image on the back surface are performed in the same manner.

The sorting device 13 includes a copying machine main body 11.
The copies ejected from the trays are stored in trays 77 ₁ , 77 ₂ , and 77 _3.
.., Or copies in trays 77 ₁ , 7
7 _2, 77 or sequentially fed for each page to _3..., Or selectively feeding tray which is set in advance. In this case, the transport system 79 is driven by the motor 78 and the transport system 79 is driven.
Copier is conveyed copied from the main body 11, each tray 77 _1, 77 _2, 77 _3, ... of the pawl (not shown) located near the entrance is switched selectively each tray 77 ₁ copy by the pawl by, 77 _2, 77 ₃ are ... selectively guided.

FIG. 3 shows an electrical control unit of the entire embodiment. The copying machine body 11 includes a main control unit 82 including a main control board having a processor (MPU) 81,
A scanner control unit 8 comprising a scanner control plate having
4 is provided. The MPU 81 controls the image forming sequence by controlling each load so that the above-described copying operation is performed, and performs the system-related control of the present embodiment as is well known. The CPU 83 controls the scanner section so that the above-described operation of the scanner section is performed.

The MPU 81 and the CPU 83 are connected by a serial interface (RS232C) and exchange data with each other. The memory control board 85 controls a hard disk drive 86 as an external storage device in accordance with an instruction from the main control board 82 to record and reproduce data. The operation unit 87 has various keys operated by the user and a display for performing various displays, and is controlled by the scanner control plate 84.

The automatic document feeder (ADF) 12 and the scanner motor 88 are controlled by a scanner control plate 84, and the Xe lamp 15 is controlled by the scanner control plate 84 via a stabilizer 89. The reading control board 90 is
The image signal from D23 is output to A through ASICs 91 and 92.
After A / D conversion by the / D converters 93 and 94, the data is transferred to the image processing board 24 via the scanner control board 84. APS
Reference numeral 95 denotes an automatic paper selection unit for automatically selecting a transfer paper, and a scanner control plate 84 is a paper supply device in which the transfer paper selected by the automatic paper selection unit is stored when the user does not select a paper supply device. Select

The LD control board 96 drives the semiconductor laser 98 of the writing section in accordance with an instruction from the main control board 82 in synchronism with the synchronizing signal from the synchronism detecting sensor 97 by means of an image signal from the image processing board 24, and The motor 31 is controlled by a main control plate 82. DC power supply /
The AC control board 99 includes the main control board 82, the motherboard 1
00, I / O control board 101, sorter / stapler 13,
A predetermined DC voltage or AC voltage is applied to the high-voltage power supply 102, the main motor 103, the fixing heater 104 of the fixing device 56, and the like. The high-voltage power supply 102 applies a developing bias voltage to the developing rollers of the main developing device 40 and the sub developing device 41, and applies a high voltage to the charging charger 39, the transfer charger 52, the separation charger 53, and the like. The main motor 103 rotates the photosensitive drum 25 and the like, and the sorter / stapler 1
3, high voltage power supply 102, main motor 103, fixing device 5
The fixing heater 104 and the double-side reversing unit (double-side drive plate) 14 of the I / O control plate 10
1 is controlled via

A paper feed control plate 105 is provided in accordance with an instruction signal input from the main control plate 82 via the I / O control plate 101, a paper feed raising motor of the paper feed devices 44 to 46, a paper feed clutch, and a manual feeder. Paper clutch, intermediate clutch, manual feed solenoid, mass feeder (LCT) 106,
The paper feed bank 107 is controlled, and a detection signal from each sensor of the paper feed device is sent to the main control board 8 via the I / O control board 101.
Output to 2.

Here, in the paper feeding devices 44 to 46, the transfer paper in the paper feed cassette is placed by the paper feed raising motor such that the uppermost transfer paper in the paper feed cassette reaches the paper feed position. The paper loading plate is lifted, and the paper feed rollers 47 to 49 rotate when the paper feed clutch is turned on. In addition, LCT10
6 and the paper supply bank 107 are selectively connected to the copying machine main body 11 and transfer the transfer paper to the registration rollers 5 via a vertical conveyance path.
0 is fed. Opening / closing means is provided in the vertical transport path.

Each sensor of the paper feeder includes a sensor for detecting the absence of transfer paper in each paper feeder, a sensor for detecting the absence of manual transfer paper, a sensor for detecting that the paper feed cassette has been raised to the upper limit position, Sensors for detecting the amount of transfer paper remaining in each paper feeder 44 to 46, sensors for detecting the size of transfer paper in each paper feeder, sensors for detecting the size of manual transfer paper, transfer in each paper feeder Sensor to detect paper jam,
The sensor includes a sensor for detecting a jam of the manual transfer paper, a sensor for detecting the length of the manual transfer paper, a sensor for detecting the setting of the manual transfer paper, and a sensor for detecting the opening and closing of the opening and closing means provided in the vertical conveyance path.

The semiconductor laser 98 emits a plurality of laser beams, and the light source unit including the semiconductor laser 98 is an LD.
The pitch in the sub-scanning direction (the rotation direction of the photosensitive drum 25) of the laser beam irradiated on the photosensitive drum 25 by being rotated by the rotation motor 108 is adjusted. Further, the LD rotation HP sensor 109 detects that the light source unit is located at the home position.

The detection signal from the LD rotation HP sensor 109 is sent to the main control board 82 via the I / O control board 101, and the main control board 82 receives the L signal via the I / O control board 101.
The D rotation motor 108 is controlled. Also, the main control board 8
Reference numeral 2 controls, via an I / O control board 101, an electrical cooling fan for cooling the electrical components, a main body cooling fan 110 for cooling the copier main body 11, a key counter and a total counter 111, and a static elimination lamp 59.

The main control board 82 exchanges signals with the key card and coin rack 112 and the customer support service section (CSS) 113 via the I / O control board 101. The CSS 113 is connected to the center via a telephone line, transmits various information such as the number of copies and the size of transfer paper used in the present embodiment to the center, and provides the user with services such as toner replenishment and transfer paper replenishment at the center. It is for. Also, the main control board 82
Are a sensor 114 for detecting the opening and closing of the front cover of the copying machine body 11, a P sensor 60, a T sensor for detecting the toner concentration of the developer in the main developing device 40 and the sub developing device 41, a toner replenisher 42, A detection signal from a toner full sensor and a transfer contact / separation HP sensor for detecting that the transfer paper 43 is full, a fixing discharge sensor for detecting that the transfer paper has been discharged from the fixing device 56, and a transfer paper of a discharge section are full. The detection signal from the full-sheet-discharge sensor and the registration sensor 51 for detecting that the condition is satisfied is taken in through the I / O control plate 101.

Further, the main control plate 82 is
Switch solenoid (SOL) for driving the sheet discharging switch, and a sheet discharge switching solenoid (SOL) for driving the sheet
L), the registration clutch (CL), the transfer contact / separation CL, and the toner supply motor are controlled via the I / O control plate 101.
Here, the registration clutch is a clutch that connects the registration roller 50 to a drive source, and the toner replenishers 42 and 43
Are operated by toner supply motors.

An expansion board mounted on the motherboard 100 is a facsimile machine having a facsimile function.
An application extension unit for realizing a composite function comprising a controller unit (FCU) 115, a printer application board 116, and a scanner application board 117. FLASHRO as a rewritable program storage memory.
M.

The FCU 115 transmits the image data from the main control board 82 to the other party via the public line, receives the image data transmitted from the other party via the public line, and sends it to the main control board 82. In the facsimile mode, the main control board 82 transmits the image signal in the image memory to the FCU 1
15 to the other party through the public line, and the FCU 115
Is temporarily stored in an image memory and then transferred to a plotter section of the copying machine main body 11 to form an image on transfer paper as described above.

In the printer mode, the printer application board 116 converts external image data into image data and sends it to the main control board 82.
Is temporarily stored in the image memory and then transferred to the plotter section of the copying machine main body 11 to form an image on transfer paper as described above. In the scanner mode, the main control board 82 takes in an image signal from the image processing board 24 and stores it in an image memory.

FIG. 1 shows the structure of the main control plate 82. The main control board 82 includes an MPU 81 that controls the entire machine according to the present embodiment, and an MPU peripheral LSI 121 that has an interface function with a UART and peripheral devices.
For performing image processing and image data flow control
22, the image memories 123 and 124, and compresses and writes the image data into the image memories 123 and 124, reads out the image data from the image memories 123 and 124, decompresses them, and performs various operations of the image memories 123 and 124. An LSI 125, flash ROMs 126 and 127 as program / data areas of the MPU 81,
81, a DRAM 128 as a work area, and an nvRAM 129 as a nonvolatile memory for storing adjustment data and an operation mode of the present embodiment.

The MPU 81 includes a flash ROM 126,
The above operation is performed by using the work area of the DRAM 128, the adjustment data and the operation mode in the nvRAM 129 by the program / data in the 127, and the image memory 1
LSIs 121, 122, 125 for 23, 124
The image data is read and written via.

The main control board 82 has a plurality of connectors mounted thereon. The interface (I / F) CN 302 with the scanner control board 84, the I / FCN 303 with the LD control board 96, and the application expansion board 11
I to motherboard 100 to connect 5 to 117
/ FCN304, CN305, I / FCN307 with I / O control board 101, IC card connector CN308,
Socket CN310 for driving polygon motor 31 and socket CN31 for expanding image memory of memory control LSI 125
1. An option board I / FCN 313 for memory application is prepared.

Here, when an IC memory card as an external memory is connected to the IC card connector CN 308, the main control board 82 writes the contents of the IC memory card into the FLASHROMs 126 and 127,
Alternatively, the reverse operation is performed.

FIG. 4 shows the FLASH control section of the main control board 82. MPU81 and FLASHROM126,12
7 and an IC memory card, a data bus 131 and an address bus 132 are directly connected.
126, 127 and the control signal of the MPU 81
XCSR of chip select module built in
The signals of OM1 to OM4 and R / XW are decoded by the decoder 130 and XWFCCD, XOECRD, XWE
ROM1,2, XOEROM1,2 signals are created,
These are the IC memory card and FLASHROM 126,
127. Therefore, the FLASHROM 126,
127 and the IC memory card are similarly allocated in the memory space of the MPU 81.

Next, the procedure for rewriting the flash ROMs 126 and 127 will be described with reference to the flowchart of FIG. The MPU 81 receives the FLAS from the operation unit 87.
FLASHRO by input signal of HROM rewrite instruction
In the M rewrite mode, first, it is checked whether or not an IC memory card is connected to the IC card connector CN308.
When the memory card is not connected, the operation unit 87 is caused to display that the IC memory card is not connected, and the FL is displayed.
The process in the ASHROM rewrite mode is ended.

When an IC memory card is connected to the IC card connector CN 308, the MPU 81 reads out an identification code stored in a predetermined specific area of the IC memory card, and similarly reads the FLAS.
The unique identification codes of the main control board 82 and the expansion boards 115 to 117 stored in specific areas of the HROMs 126 and 127 are read, and these identification codes are compared.

When the identification code of the identification code stored in a specific area of the IC memory card matches the identification code of the main control board 82, the MPU 81
The contents of the flash ROMs 126 and 127 are rewritten by executing a rewriting routine of the SHROMs 126 and 127 to read data stored in the IC memory card and writing the data into the flash ROMs 126 and 127.

When the identification code of the identification code stored in the specific area of the IC memory card matches the identification code of any of the extension boards 115 to 117, the MPU 81 changes the identification code to the IC memory. A rewrite command is transmitted to the extension board that matches the identification code of the identification code stored in the specific area of the card, and then data from the IC memory card is transmitted, and the program mounted on the extension board is stored. The contents of the FLASHROM as the memory for use are rewritten, and when the rewriting is completed, the processing of the FLASHROM rewriting mode is ended. When a rewrite command is transmitted from the MPU 81, the extension board
By writing the data from the IC memory card transmitted from U81 to the built-in FLASHROM,
Rewrite the contents of the ASHROM.

The MPU 81 operates when the identification code of the identification code stored in the specific area of the IC memory card does not match any of the unique identification codes of the main control board 82 and the expansion boards 115 to 117. To display a non-applicable message on the operation unit 87,
The processing in the LASHROM rewrite mode ends.

FIG. 6 shows an interface between the main control board 82 and an extension board, for example, a facsimile controller unit 115. The input side and the output side of the data line of the image signal are independent. When a normal image signal is exchanged between the main control board 82 and the facsimile controller unit 115, the selectors 133 to 136 are selected on the image signal side (VIDEO side), and the image processing LSI 122 of the main control board 82 is selected. Flows through the selectors 133 and 135 to the image processing LSI 137 of the facsimile controller unit 115, and the image signal from the image processing LSI 137 flows to the image processing LSI 122 through the selectors 136 and 134.

Facsimile controller unit 1
When rewriting the contents of the built-in FLASHROM, the MPU 81 of the main control board 82
33 and 134 are switched to the data side (DATA side), and the facsimile controller unit 115 is switched.
To rewrite the contents of the built-in FLASHROM
The facsimile controller via the PU peripheral LSI 121, the UART transmission line 137, and the MPU peripheral LSI 138 of the facsimile controller unit 115
The MPU 139 of the unit 115 informs the
U139 switches the selectors 135 and 136 to the data side.

Since the I / F between the main control board 82 and the facsimile controller unit 115 uses a Centronics I / F, the strobe signal STROBE is used as a write control signal, and the MPU
81 indicates that STROBE is an MPU peripheral LSI 121, UA
The signal is sent to the MPU 139 via the RT transmission line 1140 and the MPU peripheral LSI 138. After that, the MPU 81
The data from the memory card flows to the MPU 139 via the selectors 133 and 135.

In FIG. 6, reference numeral 141 denotes an MPU 81.
Is a UART receiving line for receiving signals from the MPU 139 via the MPU peripheral LSIs 138 and 121. Also, the facsimile controller unit 11
Extension boards 116 to 117 and the main control board 82 other than 5
Of the main control board 82 and the facsimile controller unit 115 are also configured in the same manner.

As described above, this embodiment is an embodiment of the invention according to claim 1 and is mounted on the main control plate 82 as a control unit for controlling the operation of the entire machine, and is rewritable. In addition, FLA as a program storage memory in which a unique identification code of the control unit 82 is stored.
SHROMs 126 and 127, an IC memory card as an external memory storing a program for rewriting the program storage memories 126 and 127 and an identification code, and an IC as a means for connecting the control unit 82.
The card connector CN 308 compares the unique identification code of the control unit 82 with the identification code stored in the external memory. Only when these identification codes are equal, the program stored in the external memory is Since the MPU 81 is provided as means for writing to the program storage memories 126 and 127, erroneous writing of a program from the external memory to the program storage memory on the control unit can be prevented, and erroneous writing due to erroneous writing can be prevented. NvRAM as non-volatile memory by executing program
129 can be prevented from being destroyed.

This embodiment is an embodiment of the second aspect of the present invention, and in the image forming apparatus according to the first aspect, a plurality of expansion boards 115 to 117 are added to provide a predetermined composite function. Can be realized, and the extension board 1 is previously stored in a flash ROM as a rewritable memory inside each of the extension boards 115 to 117.
The unique identification codes 15 to 117 are respectively stored, and the identification codes stored in the internal memories of the plurality of expansion boards 115 to 117 are stored in the external memory connected to the control unit 82. MPU 81 as a means for writing a program stored in the external memory to the internal memory of the expansion board that matches the identification code specified, the writing port can be provided in one place, and the operability is improved. In addition, it is possible to prevent erroneous writing of a program from the external memory to the program storage memory on the control unit due to an error in the external memory for the control unit and the extension board.

This embodiment is an embodiment of the third aspect of the present invention, and in the image forming apparatus according to the second aspect, the program stored in the external memory is stored in the extension board 115-117. Since the data communication means for writing to the internal memory is also used as the signal line of the image data, it can be realized at low cost without adding a new I / F, and can store the program on the control unit from the external memory at high speed. The program can be written to the memory.

[0068]

As described above, according to the first aspect of the present invention, it is mounted on the control unit for controlling the operation of the entire machine, is rewritable, and stores the unique identification code of the control unit. Means for connecting the control unit to an external memory storing a program for rewriting the program storage memory, a program for rewriting the program storage memory, and an identification code; a unique identification code for the control unit; Means for comparing the identification codes stored in the memory with each other and writing the program stored in the external memory to the program storage memory only when these identification codes are equal. Erroneous writing of the program to the program storage memory on the unit can be prevented, and It is possible that the contents of the nonvolatile memory can be prevented from being destroyed.

According to the second aspect of the present invention, in the image forming apparatus according to the first aspect, a configuration capable of realizing a predetermined composite function by adding a plurality of extension boards is provided.
The unique identification code of each of the extension boards is stored in advance in a rewritable memory inside each of the extension boards, and the identification code stored in the internal memory of the plurality of extension boards is the There is provided means for writing the program stored in the external memory to the internal memory of the expansion board that matches the identification code stored in the external memory connected to the control unit. Thus, operability can be improved, and erroneous writing of a program from the external memory to the program storage memory on the control unit due to an error in the external memory for the control unit and the expansion board can be prevented.

According to a third aspect of the present invention, in the image forming apparatus according to the second aspect, the data communication means for writing the program stored in the external memory to the internal memory of the extension board is provided. Since this signal line is also used as a signal line, it can be realized at low cost without adding a new I / F, and can write a program from an external memory to a program storage memory on the control unit at high speed.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a control plate according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view schematically showing the embodiment.

FIG. 3 is a block diagram showing an electrical control unit of the whole embodiment.

FIG. 4 is a diagram illustrating a FLASH of a main control plate according to the embodiment;
It is a block diagram showing a control part.

FIG. 5 is a flowchart showing a rewriting procedure of the flash ROM in the embodiment.

FIG. 6 is a block diagram showing an I / F between a main control board and a facsimile controller unit in the embodiment.

[Explanation of symbols]

 81, 139 MPU 82 Main control board 115-117 Expansion board 121, 138 MPU peripheral LSI 122, 137 Image processing LSI 126, 127 FLASHROM 129 Non-volatile memory

Claims (3)

[Claims] 1. A program storage memory which is mounted on a control unit for controlling the operation of the entire machine, is rewritable, and stores a unique identification code of the control unit. Means for connecting an external memory storing a program for rewriting and an identification code to the control unit, and comparing the identification code unique to the control unit with the identification code stored in the external memory; Means for writing a program stored in the external memory to the program storage memory only when the identification codes are the same. 2. An image forming apparatus according to claim 1, wherein a predetermined composite function is realized by adding a plurality of extension boards, and said rewritable memory is internally stored in each of said extension boards in advance. A unique identification code of each of the extension boards is stored, and an identification code stored in an internal memory of the plurality of extension boards is stored in an external memory connected to the control unit. An image forming apparatus comprising: means for writing a program stored in an external memory into a memory inside an expansion board that matches a code. 3. The image forming apparatus according to claim 2, wherein the data communication means for writing the program stored in the external memory to the internal memory of the extension board is also used as a signal line of the image data. Characteristic image forming apparatus.